LONDON (Reuters) - The government
tried to cover up one of the country's most famous sightings of an Unidentified
Flying Object (UFO), a parliamentary watchdog has ruled.

The "Rendlesham Files", which were finally
published on the Internet on Sunday, contain eye witness accounts by U.S.
Air Force officers at a military base close to Rendlesham Forest, near
Ipswich in Suffolk, who saw a brilliantly lit object land in the forest
in December 1980.

The incident is widely regarded as one of the most significant-ever
UFO sightings -- the British equivalent of the 1947 incident in which a
spacecraft supposedly crashed at Roswell, New Mexico, with aliens aboard.

Several people had complained to the parliamentary ombudsman,
Ann Abraham, that the Ministry of Defence had refused to divulge full details
of the Rendlesham witness accounts. Abraham ruled the ministry had "withheld
three documents relating to reported sightings of unexplained aerial phenomena
in 1980 -- the Rendlesham Forest UFO incident".

A ministry spokeswoman however said the files had not
been deliberately withheld and had always been available to anyone who
asked.

In late December 1980, U.S. officers investigating what
they thought must be a crashed plane in the forest saw a triangular "strange
glowing object" that sent farm animals into a frenzy.

"The object was described as being metallic in appearance
and triangular in shape, approximately two to three metres across the base
and approximately two metres high," reads a report in the file by
Deputy Base Commander Lieutenant Colonel Charles Halt.

"It illuminated the entire forest with a white light,"
he added. "The object itself had a pulsing red light on top and a
bank of blue lights underneath. The object was hovering, or on legs."

Sceptics say the witnesses were merely seeing the beam
from a lighthouse on the nearby coast.

But the report adds that the next day three depressions
seven feet (two metres) in diameter were found in the grass and that readings
of beta and gamma radiation were ten times higher than normal. Disturbances
were also noted on airforce radar at the time.

Later in the night, a second UFO was seen, described
as a red sun-like light. "At one point it appeared to throw off glowing
particles and then broke into five separate white objects," said the
file.

A Ministry of Defence (MoD) memo in the file notes that:
"No evidence was found of any threat to the defence of the United
Kingdom. In the absence of any hard evidence, the MoD remains open minded."

Until last week, only around 20 members of the public
had seen the file. The government said it would also be publishing other
files on reported UFO sightings on www.mod.uk.

The Rendlesham File contains an MoD memo suggesting British
requests for audio tapes made by the American officers at the time were
brushed aside by the U.S. Later reports by UFO enthusiasts claimed that
photographs and tapes were taken away by senior U.S. officers.